“But downstream dispersal doesn’t spread zebra mussels to new river basins – boats do — and boats can spread them downstream more quickly. Texans can protect other river basins and prevent zebra mussels from spreading more quickly to other reservoirs by being extremely diligent about cleaning, draining and drying their boats and other gear every time they visit any lake or river,” TPWD aquatic invasive species team leader Monica McGarrity said.

Most Texas water bodies are at high risk of zebra mussel invasion, and zebra mussel DNA was identified in at least 10 other water bodies in the state during routine sampling in 2017.

The presence of zebra mussel DNA doesn’t confirm that the mussels or larvae are in a specific lake but it alarms biologists.

“The DNA hits also underscore the importance for boaters to thoroughly clean, drain and dry their boats and gear when leaving any lake in Texas, not just at the 22 we have classified as infested, positive or suspect,” Inland Fisheries regional director Brian Van Zee said.